Method and system for scheduling the discharge of distributed power storage devices and for levelizing dispatch participation

ABSTRACT

Disclosed is a computerized method for dispatching energy from distributed resources in a discharge event so that the energy stored in individual devices is ilevelized, or so that an operator request is met. Evaluation of event parameters may be deferred. The method may be utilized to dispatch energy from plug-in electric vehicles. Systems and methods to account for electricity dispatched to or from electric vehicles are disclosed. Systems and methods for incentivizing consumers to participate in a dispatch event or curtail energy use are disclosed.

This application is a continuation of U.S. patent application Ser. No.12/118,644 filed May 9, 2008, which claims the benefit of U.S.Provisional Application No. 60/916,861, entitled Method and System forScheduling The Discharge Of Distributed Power Storage Devices And ForLevelizing Dispatch Paticipation, filed May 9, 2007, which are hereinincorporated by reference in their entirety.

This application includes material which is subject to copyrightprotection. The copyright owner has no objection to the facsimilereproduction by anyone of the patent disclosure, as it appears in thePatent and Trademark Office files or records, but otherwise reserves allcopyright rights whatsoever.

FIELD OF THE INVENTION

The present invention relates in general to the field of electric powerdistribution systems, and in particular to methods and systems for thedischarge of stored energy from distributed energy resources.

BACKGROUND OF THE INVENTION

Work scheduling of centralized electricity generation, such as fromelectricity power plants, is known. Such work scheduling includes, e.g.,scheduling of discharge and curtailment events. However, known solutionsare poorly applicable for determining optimal schedules for distributedenergy resources, such as distributed consumer electrical powergeneration devices and distributed power storage devices such asbatteries in consumer power control appliances. Such distributed energyresources are described in U.S. patent application Ser. No. 11/968,941entitled “Utility Console for Controlling Aggregated Energy Resources”filed Jan. 3, 2008, which is incorporated herein by reference in itsentirety. Known solutions for scheduling discharge and curtailmentevents are particularly inapplicable to distributed energy resourceswhere the quantity of such resources is relatively large and where thedischarge capability varies for each unit.

One distributed energy resource is plug-in electric vehicles (“PEVs”). APEV is any vehicle such as a car, truck, bus, motorcycle, etc that drawselectricity from a power distribution network (“grid”), stores theelectricity through some means, and uses electricity to power thevehicle. A PEV may come in a variety of forms, including hybridizeddrivetrain and electric-only drivetrain vehicles.

Hybridized drivetrain vehicles use a combination of electricity drawnfrom the grid and on-board motive force that may be used to both drivethe vehicle and/or as a generation source to extend the range of thevehicle by augmenting the on-board electricity storage. The on-boardmotive force/generation source can include a variety of power plantsincluding gasoline, diesel, bio-fuel combustion engines driving agenerator. Or the on-board electricity generation may come from moreadvanced means such as fuel cells that use hydrogen, or other fuels togenerate a flow of electricity. In the future, it is possible that somepart of the electricity generation will come from photo-voltaicgeneration, kinetic energy capture, or advanced technology means. Ingeneral, most hybridized drivetrains generate additional electricity foron-board storage through regeneration by using the motor as a generatorduring coasting and braking operations.

Electric-only drivetrain vehicles use only an electric motor(s) toprovide motive force coupled with sufficient electricity storage toprovide suitable driving characteristics and range. As with thehybridized drivetrain, the energy storage may be in a variety of forms:chemical batteries, electrostatic capacitive storage, or a combinationof the two. Other forms of energy storage may include electro-kineticsuch as fly wheels, or thermal methods that rely upon the energycaptured and released during phase-change operations. The electric-onlydrivetrain may use regeneration (see above) to capture electricity forstorage to extend the range of the vehicle. In addition, there is thepotential to use extra-vehicular means to generate or transferelectricity into the car for direct motive force or to supplement theenergy storage. Examples of this include magneto-coupling built intoroadways, linear generators embedded into roadways, or other means notyet contemplated that involve interaction between the vehicle and itsenvironment.

The amount of electricity storage on the vehicle varies as to whether itis a hybridized or an all-electric configuration. Current developmentefforts by the automotive community indicate that a hybridizeddrivetrain requires 12-16 kWh of on-board energy storage and that allelectric vehicles will require 50-60 kWh of energy storage, dependingupon desired range and performance characteristics. The primary limitingfactors of the storage capacity remain both physical size, weight, andcost of the storage medium. The secondary limiting factors will becrashworthiness, replenishment times, and electrical infrastructurewithin the home or at commercial charging stations. As new materials andmethods come to market, the on-board storage capacity will increase overtime with the significant possibility that an all-electric drivetrainwill be prevalent in the daily transportation vehicles on the road.

While the PEV has tremendous consumer and societal benefits, itpotentially has a significant negative impact on electric gridoperations. This is due to the charging requirements of the vehicle andinnate consumer behavior. For example, a PEV that has 16 kWh of energystorage that is depleted 80% every day will require 12.8 kWh ofreplenishment before use again the next day. A typical 110V wall outletof 20 amp capacity—with many only at 15 amps—limits the current draw toroughly 2000 watts. Charge management algorithms for chemical batteriesare non-linear with a decrease in current flow into the batteries whenthey are both near empty and near full. As such, the charge time isextended beyond the six hours normally expected in this case if thecharging cycle was linear. The amount of “stretch” required for optimalcharge management varies by battery type and manufacturer.

The combination of the high draw rate (2000 watts), the time required(6-8 hours) to replenish the stored energy, and the timing of theconsumer places a significant burden on the electric power deliverysystem when millions of PEVs are on the road. Once the energy storagedevice is in “bulk charge” mode—neither almost empty nor almost full—itis drawing current at a 100% duty cycle. This is unlike any other majorconsumption item within most households except lighting, which generallyaccounts for a relatively small percentage of electricity consumption.

Consumer driving habits factor into the problem as well. Assuming thatPEVs are used as commuter vehicles, then the typical driving pattern isto unplug in the morning, drive 30-50 miles per day round trip, and thencome home between 6 pm and 7 pm to plug the vehicle back into the gridfor replenishment. When compared to the average peak draw of a householdover the period of one hour, the PEV at 110V/20 A current floweffectively doubles the consumption of the house during a typicalevening peak demand period. This level of consumption is not planned forin the generation or distribution capacity of electric serviceproviders. With as little as a few hundred PEVs on a distributionfeeder, there can be significant delivery issues for the electricutility. With as little as a few thousand within a service territorycharging at peak, there can be significant issues related to generationcapacity.

Electric only drivetrains with 50-60 kWh of storage exacerbate thisproblem further. Normal daily driving habits will probably not drain thestored energy beyond that expected by the hybridized drivetrain.However, a longer daily use pattern, or long trips will require up tothree times the replenishment time at 110V/20 A, which results in up to18 hours of charge time, which is not practical for most applications.While the circuits to support replenishment can be upgraded to 220V athigh current limits, the energy storage characteristics will determinehow much current can be flowed into the device without damage. However,the larger the current draw, the larger the problem for effective gridmanagement.

SUMMARY OF THE INVENTION

In an embodiment, the invention provides a computerized method fordispatching energy from distributed resources in a discharge event sothat the energy stored in individual devices is levelized. A dispatchrequest including an amount of power required during a dispatch eventand a duration of the event is received, and accomplishability of thedispatch request is determined. Individual resource participation in thedispatch event is determined utilizing rules that set the amount ofenergy to be discharged from each participating resource so as to keepthe level of energy stored in each individual resource equal relative tothe energy level of other participating resources. Individual resourcedispatches are then scheduled, and the resources are commanded todispatch energy at their appointed time.

In another embodiment, the invention provides a computerized method fordispatching energy from distributed resources to meet an operatorrequest. A dispatch request including an amount of power required duringa dispatch event and a duration of the event is received, andaccomplishability of the dispatch request is determined. Individualresource participation in a planned dispatch event is then determined,and individual resource dispatches are scheduled at a future time. Atthat time, the individual resources are commanded to dispatch energy.

In another embodiment, the invention provides a computerized method fordispatching energy from distributed resources that defers evaluation ofevent parameters. A dispatch request is received, and a determination ismade of the accomplishability of the dispatch request. Individualresource participation in a planned dispatch event is then determined.Individual resource dispatches are scheduled at a future time.Accomplishability of the dispatch request is redetermined prior to saidfuture time, and individual resources are commanded to dispatch energybased upon such redetermination of accomplishability.

In another embodiment, the invention provides a computerized method fordispatching energy from plug-in electric vehicles. A dispatch request isreceived, and accomplishability of the dispatch request is determined. Adata network is used to determine availability of individual PEVs at arequested future time for a dispatch event. Resource participation in aplanned dispatch event is determined based upon such availability.Individual PEV dispatches are scheduled at the future time. Individualresources are commanded to dispatch energy at such time.

In another embodiment, the invention provides a method of receiving andtransmitting data to account for electricity flowing through a chargingreceptacle to or from a storage device in an electric vehicle. Aclearinghouse receives a request for authorization that has beengenerated in response to connection of an electric vehicle to a chargingreceptacle, the request for authorization including identification datasufficient to identify a first account of a first utility companysupplying electricity to said charging receptacle and to identify anelectricity billing account associated with an account holder at asecond utility company. A determination is made that the account holderis authorized to charge said account for electricity drawn from thecharging receptacle. Data is transmitted to enable the flow ofelectricity at the charging receptacle. Data indicating the amount ofelectricity drawn from the charging receptacle to charge the storagedevice in said electric vehicle is received by the clearinghouse. Thedata is used to cause the account associated with the first utilitycompany to be credited and the utility company account to be charged.

In other embodiments, the invention provides systems and methods forincentivizing consumers to participate in a dispatch event or curtailenergy use.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects, features, and advantages of theinvention will be apparent from the following more particulardescription of preferred embodiments as illustrated in the accompanyingdrawings, in which reference characters refer to the same partsthroughout the various views. The drawings are not necessarily to scale,emphasis instead being placed upon illustrating principles of theinvention.

FIG. 1 illustrates one embodiment of a system which is capable ofsupporting the dispatch of energy from distributed energy resources;

FIG. 2 shows a block flow diagram illustrating the steps of levelizingand scheduling the dispatch of distributed energy resources;

FIG. 3A illustrates the dispatch of hypothetical distributed resources;

FIG. 3B shows a representation of hypothetical dispatch requests fordistributed resources;

FIG. 3C illustrates a levelized dispatch of distributed resources;

FIG. 4 shows a block flow diagram of a method of scheduling the dispatchof distributed resources;

FIG. 5 illustrates a method of scheduling the dispatch of distributedresources;

FIG. 6 shows another method of scheduling the dispatch of distributedresources;

FIG. 7 illustrates a system capable of supporting the dispatch of energyfrom mobile distributed energy resources;

FIG. 8 shows a block flow diagram of a method of accounting for atransaction involving the dispatch of energy from distributed energyresources;

FIG. 9 shows one example of a user interface; and

FIG. 19 shows another example of a user interface.

DETAILED DESCRIPTION

The present invention is described below with reference to figures,block diagrams and operational illustrations of methods and devices tomanage power generation, consumption, and storage. It is understood thateach block of the block diagrams or operational illustrations, andcombinations of blocks in the block diagrams or operationalillustrations, can be implemented by means of analog or hardware andcomputer program instructions. These computer program instructions canbe provided to a processor of a general purpose computer, specialpurpose computer, ASIC, or other programmable data processing apparatus,such that the instructions, which execute via the processor of thecomputer or other programmable data processing apparatus, implements thefunction/acts specified in the block diagrams or operational block orblocks. In some alternate implementations, the functions or acts notedin the blocks can occur out of the order noted in the operationalillustrations. For example, two blocks shown in succession can in factbe executed substantially concurrently or the blocks can sometimes beexecuted in the reverse order, depending upon the functionality or actsinvolved.

The operator of a utility control system, if given a request to dispatchor curtail some aggregate total amount of energy (or power) at somepoint in the future, may attempt to meet this request by commanding adistributed set of energy resources to individually produce or curtailat such future point a certain amount of energy (or power). Examples ofenergy resources may include various types of batteries. Energyresources may also include devices or systems for generatingelectricity. Other examples of energy resources may include powerconsuming devices, such as appliances, which if turned off or removedfrom the grid reduce the amount of demand for power from the grid, thusfreeing up grid capacity. These may all be referred to as “distributedresources” as well.

FIG. 1 illustrates one embodiment of a system and network which iscapable of supporting the dispatch of energy from distributed energyresources. An electrical utility has an operations control center 105.Within the control center 105, one or more servers 110 host applicationssoftware which implement various applications including a utilityconsole. The servers 110 provide information to a display device 115capable of supporting a user interface. The servers 110 are additionallyconnected to one or more storage devices 120 which may provide forstorage of one or more actively used databases or which may providebackup or archiving of data collected by the servers. An example ofapplications software described above is disclosed in U.S. patentapplication Ser. No. 11/968,941 entitled “Utility Console forControlling Aggregated Energy Resources” filed Jan. 3,2008, which isincorporated herein by reference in its entirety.

The servers are connected to the local network 125 of the operationscontrol center. The local network 125 is connected to the Internet 350though conventional routers and/or firewalls 130. The local network 125may also be connected to a common carrier wireless network or a privatenetwork 300. The local network 125 is also connected to a wide areanetwork 200 which is connected to one or more power generation points210.

Power consumers 400 in the service territory of the utility have one ormore power control appliances 410. Power control appliances 410 mayinclude one or more energy storage units, such as batteries (not shown).Power is transmitted to the consumer 400 over transmission lines 220which form part of the local power grid. Power drawn by a consumer fromthe grid may be supplied, in part, by one or more power generationpoints 210, or may originate in remote locations (not shown). Powerenters the consumer premises at a meter 420 and is routed to the powercontrol appliance 410, which may comprise an onboard computer, energystorage, and an inverter/charger.

Power transmission lines 220 can additionally support transmission ofdata between the power generation point 210 and power consumer 400. Thepower generation point 210 is connected to the operations control center105 through the wide area network (WAN) 200 and is connected toconsumers 400 though power transmission lines 220. Thus, the servers 110may receive data from or transmit data or commands to distributed energymanagement controllers 410 using the Internet 350, the wireless network300, or the WAN 200.

The power control appliance 410 may be configured to control one or moreelectrical circuits which supply power to one or more power consumingdevices 430, such as household appliances. Power control appliance 410may also be configured to supply electricity to, or to draw electricityfrom, a mobile device capable of energy storage, such as a plug-inelectric vehicle (PEV) 460. In one embodiment, the system uses a numberof load controllers with integrated measurement and/or a communicatingthermostat (not shown). Load controllers with integrated measurement canbe installed by placing them inline with the circuit to be measured andcontrolled, and may be installed near the main load panel (though thereis no requirement to do so). Any number of load controllers withintegrated measurement may be installed at a site. The power controlappliance 410 may additionally have control connections to the powerconsuming devices 430 which allow the power control appliance 410 tocontrol the operation of the power consuming devices 430.

The power control appliance 410 may be further connected to one or morepower generation devices 440, such as solar panels, which are capable ofgenerating power. Power generated by the power generation devices 440may is routed to the power control appliance 410 for use by theconsumer. Under the control of the power control appliance 410 powergenerated by the power generation devices 440 may also be routed, inwhole or in part, to the power grid 220. It may also be stored instorage batteries, or in the storage capacity of a PEV.

The power control appliance 410 may be controlled at least in part bythe consumer using a user interface displayed on a display device 450.Display device 450 may be a mobile device capable of supporting a userinterface. Device 450 may connect directly to the Internet 350, thewireless network 300, or the WAN 200, or it may connect through powerappliance 410. Power control appliance 410 may be further controlledremotely by the utility control center 105, for example, over theInternet 350, or over a common carrier wireless network 300. In oneembodiment, the servers 110 at the utility control center 105 mayreceive and transmit data and commands to the power appliance using theInternet 350, the wireless network 300, or the WAN 200.

Further examples of power control appliances which may be used inembodiments of the system illustrated in FIG. 1 are described in U.S.Pat. No. 7,274,975, entitled “Optimized Energy Management System.”

In order to match electricity supply and demand, a utility controlsystem operator may desire to curtail load or dispatch energy fromdistributed energy resources. One method of meeting a request todispatch or curtail energy is to command individual distributed energyresources differently, based on the state of each energy resource at thetime the command is executed, while at the same time attempting toensure that the sum of all the individual actions meets the requirementsof the overall request. In addition, it is desirable to dispatch storedenergy in such a way so as to preserve as much as possible the abilityto meet subsequent dispatch requests.

FIG. 2 shows a block flow diagram illustrating the steps of levelizingand scheduling the dispatch of distributed energy resources 500. Usinginformation provided to the utility control center 105 by distributedenergy resources, such as, for example, current stored capacity and rateof discharge, a utility creates a dispatch event 510 using a controlsystem such as that described above in, for example, the utility controlcenter 105. Specifications for the dispatch event include the amount ofpower desired during the event and the duration of the dispatch event.Next, the accomplishability of the requested dispatch event isdetermined 520. Next, if the dispatch request is accomplishable, theamount of energy to be discharged from each participating unit isdetermined 530. Then, the energy dispatch of individual units isscheduled and the instructions for each distributed resource aredetermined 540. These steps are further described below. It should beunderstood that distributed energy resources can mean any device capableof storing and discharging electricity and communicating with a systemsuch as shown in FIG. 1. Distributed energy resources include the energystorage batteries of power control appliance 410, consumer powergeneration devices such as solar panels or generators, and the mobileenergy storage capabilities of PEV 460 or any other mobile energystorage device.

Given the specifications for a dispatch event, the accomplishability ofthe requested dispatch event is determined in step 520. One example ofdetermining the accomplishability of a dispatch event is discussedbelow.

For example, with reference to FIG. 3A, consider three energy storagedevices 610, 620, and 630. Devices 620 and 630 contain 1.8 kWh of storedenergy, and device 610 contains 10.8 kWh of stored energy. Each deviceis capable of releasing (dispatching) its stored energy at 3.6 kW. Arequest for a constant 10.8 kW dispatch over a 1 hour period may atfirst seem accomplishable because there is sufficient stored energy tomeet the dispatch request.

However, in fact the dispatch is not accomplishable because all threeunits would be required to dispatch at 3.6 kW (their maximum rate), andat that rate devices 620 and 630 would run out of energy in half anhour. This is shown by the inequality

$10.8 = {{K > {\sum\limits_{i}^{n}{\min \left( {Y,\frac{E(i)}{d}} \right)}}} = {{1.8 + 1.8 + 3.6} = 7.2}}$

where the rate is given by K and the duration given by d, for ndistributed energy storage devices capable of releasing stored energy ata constant rate Y, where the amount of energy stored in the i 'th device(fuel) is given by E(i). In other words, if the conditions expressed inthe inequality are met, a dispatch request is accomplishable.

If the energy level in every device were equal, then the above formulawould become

${K \leq {\sum\limits_{i}^{n}{\min \left( {Y,\frac{E}{d}} \right)}}} = {{\min \left( {{n\; Y},{\sum\limits_{i}^{n}\frac{E}{d}}} \right)}.}$

This result has several implications. First, when the energy levels instorage devices are kept equal, the rate at which energy can bedispatched over a fixed duration is maximized. Second, when the energystored in each individual device is levelized (i.e. kept equal relativeto the energy level of other available resources), a set of distributedgeneration or stored energy resources may be treated as a single largeaggregate energy storage device, with a maximum dispatch rate equal tothe sum of all the individual dispatch rates, and the stored energyequal to the sum of all the stored energies. Third, over multipledispatch events where energy is dispatched from different sub-groups ofenergy storage devices, minimizing the variance in energy storage levelsmaximizes the ability to meet future dispatch requests.

In step 530, if a dispatch request is accomplishable, the amount ofenergy to be discharged from each participating unit is determined. Forexample, with reference to FIG. 3B, consider a hypothetical situationwhere two dispatch requests are made for three distributed resources, A,B, and C, each capable of dispatching energy at 3.6 kW and all initiallyfilled with 10.8 kWh of energy. The first request is for 7.2 kW for 3hours starting at time t, and the second request is for 10.8 kW, lastingfor 1 hour, to begin at t+3 hours.

Whether the second dispatch is accomplishable depends on how the firstdispatch is performed. The first dispatch could be performed byinstructing devices A and B to dispatch at their maximum rate for thefull three hour period, as shown in FIG. 3B. However, in that case thesecond dispatch is not accomplishable because units A and B have beendrained of all their stored energy, and unit C is only capable ofdispatching at a rate of 3.6 kW. If, however, the first dispatchlevelized the stored energy of each of the three units, one example ofwhich is shown in FIG. 3C, then the second dispatch would beaccomplishable.

One example of an algorithm for determining participation informationfor an accomplishable dispatch that maximally reduces variance among thestored energy in the distributed resources is provided. Other equivalentembodiments of this specific method should be readily apparent to one ofordinary skill in the art without departing from the scope of the methoddisclosed here.

n=number of units that can be considered, Y=the rate in kW that anindividual unit can dispatch, and E(i)=a function returning the initialenergy in each unit. The specification for a dispatch request (assumedto be accomplishable) include the number of kW requested (K) and theduration of the dispatch, (d).

M:=S:={}

U:=All available units

c:=0

D[i]:=0

let R(i)=E(i)−D[i]

while(c<dK)

-   -   if(|S|=0)        -   I={iϵU:R(i)=max(R(i))}; S=I; U=U−I    -   r:=R(i):iϵS    -   e:=min((dK−c)/|S|,dY−max(D[i]):iϵS,r−max(R(i)):iϵU)    -   c:=c+e|S|    -   ∀iϵS:D[i]=D[i]+e    -   if (c<dK)        -   l:={iϵS:D[i]=dY}:=M∪I:S:=S−I        -   r:=R(i):iϵS        -   I:={iϵU:R(i)=r}:S:=S∪I:U:=U−I

Once completed, every unit for which i ϵ M ∪ S will be scheduled todispatch for

$\frac{D\lbrack i\rbrack}{Y}$

hours in order to meet the dispatch request.

Next, in step 540, when participation information has been determinedfor distributed resources in an accomplishable discharge event, theenergy dispatch of individual units is scheduled and the instructionsfor each distributed resources are determined. One example of a methodof scheduling the dispatch is provided. Other equivalent embodiments ofthis specific method should be readily apparent to one of ordinary skillin the art without departing from the scope of the method disclosedhere.

Let ScheduleDispatch(i,t_(start), t_(end)) be a function which commandsunit i to dispatch between the times t_(start) and t_(end)

  t := t₀ foreach (i ∈ I)${if}\mspace{11mu} \left( {{t - t_{0} + \frac{D\lbrack i\rbrack}{Y}} < d} \right)$ ${ScheduleDispatch}\mspace{11mu} \left( {i,t,{t + \frac{D\lbrack i\rbrack}{Y}}} \right)$  $t:={t + \frac{D\lbrack i\rbrack}{Y}}$  else   ScheduleDispatch (i,t, t₀ + d)   ${ScheduleDispatch}\mspace{11mu} \left( {i,t_{0},{t + \frac{D\lbrack i\rbrack}{Y} - d}} \right)$   $t:={t + \frac{D\lbrack i\rbrack}{Y} - {d.}}$

However, the method described above does not take into account anyminimum dispatch time which a given resource may have (e.g., because ofthe physical constraints of the storage unit). It also does not addressthe “splitting” of the dispatch of units from the end of the dispatchback to the beginning, as shown occurring with unit B in FIG. 3C, whichshows unit B scheduled for discharge from time t to time t+1, and againfrom time t+2 to t+3. A method of scheduling accomplishable dischargeswhich addresses these issues is provided below. Other equivalentembodiments of this specific method should be readily apparent to one ofordinary skill in the art without departing from the scope of the methoddisclosed here.

FIG. 4 shows a block flow diagram of a method 700 of scheduling thedispatch of distributed resources. First, resources are allocated forthe discharge event 710. Next, in step 720 the start and stop times ofthe allocated resources are redistributed to minimize any coincidentalstarting or stopping of the discharge of resources. This is done tominimize the “ripple” (i.e., fluctuation in power) on the electricalgrid which may be caused by multiple resources starting or stoppingsimultaneously. Finally, the start time of each resource is furtherchanged by the addition of a factor, to further minimize ripple. Eachstep is further described below.

In step 710, resources are allocated for the discharge event. One way toschedule resources over time is by use of a “bin-packing” method.Resources are selected to fulfill the power and duration requirements ofthe dispatch request. referring to FIG. 5, in one embodiment, dischargeintervals I(i) are scheduled for the number of participating storagedevices (N) using a bin-packing algorithm where T is the maximum lengthof a bin. In FIG. 5, a filled bin is shown at reference number 810. Manyknown bin-packing algorithms may be applied to step 710, such as thefirst-fit-first-descending algorithm.

The purpose of step 710 is to create full bins, since intervals in afull bin will not require splitting. I(i) must be equal to or less thanT, and both quantities must be specified as positive non-zero integers.Each storage unit is assumed to have constant and identical dischargerates, and thus the only parameter needed for each device is theduration of discharge. Units should be chosen such that the time quantumis also the minimum allowable discharge time of any unit.

Discharge intervals I(i) are redistributed in step 720. Full intervals(F) are reordered to remove even ordering which may be imposed by theallocation in step 710. In one embodiment, a hash function may beapplied to each interval to sort the intervals, for example, by thevector (hash(bin), hash(interval+bin)). This effectively randomizes thestart and stop times of each distributed resource to minimize “ripple”in the rate of discharge.

Next in step 730, a bin index B(i) and a starting offset time S(i) areassigned to each interval in F. Intervals for non-full bins (G) arescheduled by stacking them end-to-end, and letting them wrap around thetime window T shown in FIG. 5.

Let b=max(B)+1

Let p=0

For each G:

-   -   if p>=T:        -   p:=p−T        -   b:=b+1    -   B(i):=b    -   S(i):=p    -   p:=p+1(i)

NumBins:=b+1

If S(i)+I(i)>T, the event is split across the time window such that twodischarge events are created with start time and duration: (S(i),T-S(i)) and (0, S(i)+I(i)−T). Otherwise the discharge event is simply(S(i), I(i)).

At the end of this step, discharge events can be created from allintervals such that the total dispatch at any time does not vary morethan a ratio of (1/NumBins) across the time interval T.

Next, the start and stop times are further redistributed 730. Since theintervals are of discrete size, their boundaries will tend to line up atdiscrete time intervals. Multiple simultaneous discharge start or stopevents may create undesirable “ripple” on the grid. This can be smoothedby “tilting” the schedule. Each interval has been assigned a start timeS(i) and a bin index B(i). The tilt is defined by adding a fractionalpart F(i) to each interval:

F(i)=B(i)/NumBins

The final start time for an interval is defined as: S(i)+F(i). This willadd a ramp-up and ramp-down period for all discharging resources. Theramp-up and ramp-down time lasts exactly one time unit, and the totaldispatch power will approach a linear curve. By adding this offset, thenumber of device transitions over each time quantum is no more than(NumBins*2). Also, by adding this offset, there will be more than twodevice transitions that are less than (1/NumBins) time units apart(device transitions will always occur in pairs).

FIG. 5 shows a graphical view illustrating scheduling of the dispatch ofmultiple resources over time, where over 25% of intervals were requiredto split, such as interval 820. FIG. 6 shows a graphical viewillustrating scheduling of the dispatch of multiple resources over time,where interval lengths are uniformly distributed. Note that no intervalswere required to split.

the discharge scheduling method disclosed above can include severalvariations from that described. The method of redistributing intervalsafter the bin-packing step can be varied. Also, the “tilt” step may beomitted, eliminating the ramp-up and ramp-down time at the expense ofuneven state transitions.

The examples above assume that distributed resources have constant andidentical dispatch rates. However, the method may be adapted todistributed energy resources with varying discharge rates. For example,a slightly modified definition of accomplishability may be used in step520. Similarly, in the step of determining participation information530, distributed resources may be levelized on the basis of theirpotential discharge duration. In addition, the step of scheduling 540may be modified to account for variable discharge rates.

In one embodiment, slightly modifying the step of determiningaccomplishability 520,

$K \leq {\sum\limits_{i}{\min \left( {\frac{E_{i}}{d},Y_{i}} \right)}}$

permits a comparison of each distributed resources' individual dispatchrate Y.

Similarly, in one embodiment, in the step of determining individualresource participation 530, to levelize distributed resources withvarying dispatch rates, the stored energy in every resource should bebrought to a state where each resource has a fraction of the totalremaining energy of all available resources proportional to its dispatchrate:

$E_{i} = {\frac{Y_{i}}{\sum\limits_{i}Y_{i}}E_{total}}$

Participation information for each available resource may thus bedetermined by prioritizing resources based on each unit's potentialdischarge duration, such that the longer a resource may discharge itsstored energy, the greater its level of participation.

In addition, in one embodiment, in the step of scheduling the dispatchof individual resources 540, resources may be grouped by individual rateof dispatch and “bin-packed” by group in accordance with the methoddescribed above. This may result in a difference between the amount ofenergy requested in the dispatch request and the amount actuallydelivered in the dispatch event; however, the difference in the dispatchduration and dispatch rate decreases as the number of participatingresources increases. Specifically, the maximum %-error is:

${\% \mspace{14mu} {error}} = \frac{Y_{\max}}{K}$

where Y is the maximum output rate of any unit and K is the totaldispatch rate. For example, if 100 resources are scheduled for dispatchof a total dispatch of 330 kW and the maximum discharge rate is 6.6 kW,then the percentage error is only 2%. It will be evident that as thenumber of participating resources increases, the margin of error willdecrease.

Dispatch events may be requested in advance of the time of the desireddispatch. However, the longer the interval of time, the greater thechance that the condition of at least some distributed resources maychange. For example, distributed resources may have become disabled, orin the case of mobile energy storage, the distributed resources may beremove from the grid.

It is therefore desirable to re-evaluate the accomplishability of autility-commanded dispatch event repeatedly between the time thedispatch request is initially made and the start of the dispatch event.Such re-evaluation provides the utility control system operator leadtime to act on a notification that a previously accomplishable event isnow no longer accomplishable because of a change in circumstances.Conversely, repeated evaluation of accomplishability may also show thatan event that was unaccomplishable when scheduled has becomeaccomplishable without any further interaction by the operator. Forexample, distributed resources may have been charged, or additionalmobile energy storage may have become available for dispatch.

It is also desirable to perform an accomplishability check when a newdispatch event is created or canceled. When a new event is created, itmay affect the accomplishability of subsequent dispatch events. Forexample, creating a new dispatch event before other dispatch events maycause the later dispatch events to become unaccomplishable (for example,due to a lack of available energy). On the other hand, the cancellationof a dispatch event may make later dispatch events accomplishable.

Instructions for dispatching energy from distributed resources may becomputed based upon the state of each distributed energy resource at aspecified point in time. The determination and generation of theseinstructions may be referred to as processing the event. The generationof instructions for individual resources may be deferred until as nearto the desired start time of the event as possible, and then evaluatedfor accomplishability up to the time of event execution.

Reevaluation of accomplishability allows use of the best possible dataas an input (e.g. the data closest to the start time of the event).Reevaluation also facilitates the implementation of event cancellation,out of order event scheduling (i.e. the ability to submit events in anorder other than the one in which they will be executed); and maximumlead-time notification that an event has become unaccomplishable. Thelatest possible moment that a background task can process an event andstill expect that all the resources will be able to download and executethe corresponding instructions successfully is a function of howfrequently the control system communicates with the distributedresources. If individual resource instructions are determined too late,then there may not be enough time for the participating resources toreceive instructions prior to the dispatch event start time, and theevent will fail to fully execute.

In an embodiment, in order to both defer event evaluation and repeatedlyevaluate the accomplishability of events, a process, such as a softwareprocess (co-located with the control system in utility control center105 in one embodiment) may perform event evaluation. Instructions forindividual distributed resources are determined no later than the sum ofthe following durations prior to the start of the event; (a) thefrequency at which the background task runs (evaluation frequency); (b)the duration it takes for the background task to complete; (c) thecommunication frequency of participating resources; (d) the time ittakes for the instruction transmission to complete; and (e) otherimplementation-specific delays. Since some of these intervals may vary,implementation-specific maximum values should be chosen.

Deferred evaluation and re-evaluation of accomplishability allows thecancellation of events that have been submitted to the control system,but for which individual resource instructions have not yet beendetermined and transmitted to distributed resources. Re-evaluation ofaccomplishability also permits the scheduling of events that arecurrently unaccomplishable, but which the operator knows will becomeaccomplishable by the desired execution time, increasing the operator'sflexibility in scheduling events.

It is important for a control system operator to know what upcomingevents are not currently deemed accomplishable and thus requireremediation. In order to confirm a cancellation of an event, aconfirmation dialog may be presented, for example, that identifies theevent and displays the event's duration, start time, and end time. Anoperator may similarly be notified of a successful or an unsuccessfulcancellation of an event. For example, notifications can be displayed tothe system operator on display 115, for example, in a list that isalways visible. Notification may also be done, for example, on aschedule or dashboard view, which quickly conveys information to anoperator about events scheduled to take place in a given time period.Notifications may also be presented through visible cues on the schedulethat indicate unaccomplishable events in the time period of interest.Notification may also be performed via messaging, such as by email, fax,pager, instant messaging, or automated voice mail. In an embodiment,unaccomplishable events are distinguished from accomplishable ones bycolor, highlighting at-risk events to a system operator.

The systems and methods heretofore described may be applied to mobiledistributed resources, such as PEVs. However, the mobility of suchresources creates issues not posed by non-mobile resources.

Individual owners of PEVs may use the storage capability of the PEV aspart of an electricity use management system, such as that shown inFIG. 1. Mobile energy storage may be charged during non-peak hours, thusreducing the total cost of electricity, and electricity can be sold backto the grid during favorable conductions. An example of a system whichpermits the rescheduling of deferrable electrical consumption tooff-peak hours is described in U.S. patent application Ser. No.11/144,834, entitled “Optimized Energy Management System,” filed on Jun.6, 2005.

Individual owners of mobile energy storage systems may also permitutilities to control when the systems are charged or discharged. Mobileenergy storage may be connected to a system such as that illustrated inFIG. 1. In addition, mobile energy storage may be connected to a systemsuch as that illustrated in FIG. 7. Mobile energy storage may thusbecome another distributed energy resource on the electric grid.

However, the integration of mobile energy storage into the systemintroduces additional issues of availability of the resources andaccomplishability of a utility-commanded dispatch event. By its verynature, mobile energy storage is connected and disconnected from theelectrical grid. A dispatch might be accomplishable with the mobileenergy resources that are connected at one point in time, but may ceaseto be accomplishable if enough resources are removed from the gridwithout offsetting arrivals. Minor modifications to the steps of method500 address these issues.

To levelize and schedule the dispatch of mobile energy resources, forexample, use of a statistical method in step 520, supplemented byinformation regarding the historical arrival and departure of mobileenergy resources from a specific location, permits the determination ofthe probability that a utility-commanded event utilizing mobile energystorage is accomplishable. Such a statistical method may be used todetermine the availability of energy from mobile resources at a givenlocation. In an embodiment, a statistical method may use data such asthe number of mobile resources which historically enter and leave alocation during a given time period, the price of electricity (which maybe a price offered by a utility, as further described below), andweather conditions (such as rain or snow) or seasons (such as whether isit summer or winter) which may affect mobile resource availability. Astatistical method may also account for the day of the week and the timeof day, which may affect availability of mobile resources, for example,at a shopping mall or at a commuter mass transit station parking lot. Astatistical method may also account for holidays and for other eventswhich may affect the availability of mobile resources at givenlocations.

In an embodiment, a statistical method may use a historical distributionfor a given time period, to determine the available resources forintervals of time within the duration of a requested dispatch (eachinterval being a “timestep”), then to compute the accomplishability of arequested dispatch by determining accomplishability at each timestep.

In another embodiment, the number of arrivals may be modeled as aPoisson distribution, and the number of departures may be modeled as aset of Bernoulli trials, to provide a prediction of the number ofarrivals and departures of mobile resources at a given location.Historical arrival data, for example, for the distribution of resources,and the amount of stored energy available, may then be used to weightthe distribution of the predicted arrivals and combine theirdistribution with the number of mobile resources actually available at agiven time. The predicted distribution is then used to computeaccomplishability for each timestep. In an embodiment, a Markov ChainMonte Carlo simulator is used to rapidly compute accomplishability.

In another embodiment, the techniques described above may be combined,so that the result of the calculations is a weighted average of theresults. Relatively small timesteps may be used in the determination ofparticipation information and the scheduling of dispatch events tominimize the probability that distributed resources may becomeunavailable.

In an embodiment, a dispatch event using mobile distributed resources iscreated in utility control center 105, including specifications asdiscussed above. Next, the accomplishability of the dispatch request isdetermined using a statistical method to determine the availability ofmobile distributed resources. Next, if the dispatch request isaccomplishable, the amount of energy to be discharged from eachparticipating unit is determined, and then the energy dispatch ofindividual units is scheduled and the instructions for each distributedresource are determined. The length of the timesteps should be selectedto minimize as much as possible the number of resources which may beremoved from the electrical grid during a dispatch event, and yetreasonably minimize the computation time required. The precise length ofthe timesteps can be determined, for example, with reference tohistorical data about the arrival and departure of resources from alocation. In an embodiment, the accomplishability of a dispatch eventmay be increased by the inclusion in the calculations of a “reserve” ofmobile resources, to provide a buffer of redundancy in the determinationof accomplishability.

To account for transactions in which utilities buy stored energy from orsell energy to PEV consumers, a method is required for settling anaccount with an owner of mobile energy storage for electricity chargedor discharged or discharged at any location.

With reference to FIG. 8, when a transaction is requested 1010, firstthe PEV owner is authenticated 1020. Next, the transaction is authorized1030. Finally, the accounting for the transaction is performed 1030.These steps are further described below.

For example, a PEV owner may drive to work and park in an office parkinglot, as may be represented by the grouping of PEVs 910 shown in FIG. 7.The PEV owner may plug in his vehicle and identify himself to thecharger. This could be accomplished, for example, by use of a chargingreceptacle 920, enabled with a device permitting the owner of the mobilestorage unit to use, for example an account number or other uniqueidentifier, or swipe a credit card, for identification. Similarly, themobile resource itself may provide identifying information to thecharging receptacle. The mobile resource may communicate with thecharging receptacle using a wired connection, or using a wirelessprotocol such as WiFi, Bluetooth, or ZigBee. In an embodiment, a uniqueidentifier is associated with the mobile energy resource. Examples ofunique identifiers include an IP address (such as using IETF RFC 2460);a vehicle identification number or VIN (such as using ISO standard3779); a credit card number; and a personal identification code. Theunique identifier may be associated with the electricity billing accountof the PEV owner's home. Or, it might be associated with an accountestablished expressly for the purposes of the mobile energy resource.The unique identifier is also associated with the record of electricityconsumption or dispatch, which may include the amount of electricityconsumed or dispatched, the location, the time, and the applicable rateor rates for the electricity.

Receptacle 920 may be any type of location configured to charge ordischarge energy from a mobile energy resource, and can be, for example,at a commuter train station, or a shopping mall, or a public performancevenue, or an athletic stadium, or any other similar location. Receptacle920 may be in any location capable of accommodating mobile energyresources, and the exemplary use of a municipal or public parkinglocation is in now way intended to be limiting.

In step 1030, a transaction is authorized. For example, if the mobileresource is plugged in to recharge outside of its home serviceterritory, the utility providing the electricity may use the uniqueidentifier to confirm with the consumer's billing entity that atransaction should be permitted. A variety of levels of permission maybe granted. For example, the home billing utility might approve atransaction, but only up to a certain amount; or, the transaction couldreceive blanket approval; or, authorization could be denied, for exampleif the consumer is delinquent in bill payment, or if the consumer'sbilling utility does not have an arrangement with the utility requestedto sell or purchase electricity. Similarly, mobile devices reportedstolen may appear on a blacklist, and can be denied authorization tocharge or dispatch. Ideally authorization should occur in real or nearlyreal-time.

A transaction may also be authorized if a utility requests the dispatchof energy from the mobile resource. In that case, information about themobile resource and the owner's account information is verified, topermit a credit to be made to the mobile resource owner's account ifenergy is purchased and discharged from the mobile resource.

In step 1040, accounting for the transaction is performed. If the mobileresource is physically within the service territory of the utilityassociated with the billing account, a record of the unique identifierand electricity exchange may be readily attached to the resource owner'sbilling account. However, the location of charging receptacle may be inthe service territory of a different electrical utility company, andsettlement of a transaction in another service territory may be handleddirectly between utility companies. Alternatively, multiple electricalutilities may provide and receive information from a central clearinghouse 930, which may receive, store, and provide unique identifier andtransaction information to the relevant utilities. Information relevantto the transaction may be provided to the central clearing house overthe Internet 350. Central clearing house 930 may, for example, have adatabase of unique identifiers matched to billing electrical utilities.The central clearing house may sort records appropriately, and on abatch or real-time basis distribute them to the correct electricalbilling company for billing to the consumer. A consumer's bill couldthus contain roaming records from multiple companies combined by thehome company and presented to the consumer. Utilities may chargedifferent electricity rates for residential or commercial customers. Inan embodiment, a separate rate may be applied for “roaming” charges.

Similarly, a credit maybe applied to the mobile resource owner's accountif energy is purchased by a utility and discharged from the mobileresource. In an embodiment, a mobile resource owner parks her vehicle ata parking lot in an office building in a parking space enabled with acharging receptacle as described above. The owner swipes her credit cardon the charging receptacle to identify herself. The mobile resource thenestablishes a wireless connection to the charging receptacle andprovides information about itself. The energy stored in the mobileresource is now available for discharge. Later that day, the utility inwhose service area the mobile resource is parked initiates a dispatchrequest to the owner's mobile resource. Using the information earlierprovided, the transaction is authorized and energy is dispatched fromthe mobile resource. A credit is applied to the mobile resource owner'saccount for the amount of energy dispatched. The system may take intoconsideration multiple charge or discharge conditions. For example, theowner may have indicated to the system, through an interface on themobile resource, or through user interface an interface such as ondisplay device 450, that she wishes to fully charge the mobile resource.Alternatively, the mobile resource owner may have granted access to themobile resource such that the utility, in order to prepare for adischarge event, the utility may charge the mobile resource. The systemsand methods described above may account for multiple charge anddischarge events, and thus multiple transactions.

The pre-existing onboard systems of the vehicle may be leveraged toprovide roam charging capabilities such that a single invoice can bepresented to the customer independent of where they recharge theirvehicle. An automobile's on-board telemetry system for navigation andsafety monitoring, an example of which is the GM OnStar system, can beutilized in this respect. These systems have cellular telephone-basedcommunications systems combined with on-board diagnostics that canconvey the health and status of the vehicle along with “black box” datasuch as speed and g-force load sensor information prior to an airbagdeployment. For smart charging and roam charging applications of PEVs,these on-board telemetry systems combined with an on-board userinterface such as the navigation system, can be used to have the PEVinteract with the grid.

Such systems may be configured to operate as follows. When a user turnsoff the car, a pop up menu within the navigation screen asks the user ifthey will be plugging the vehicle in for re-charging at home or atanother location. If the user responds in the affirmative, then thesystem further asks if the user is going to “smart charge” the vehicle.If the response is again affirmative, the vehicle communicates with thenetwork operations center for the on-board telemetry system to requestthe charging parameters for that particular instance. The networkoperations center interfaces with a private service provider's networkoperations center (NOC), which in turn interfaces with the integratedresource planning system of a utility company to determine the optimumcharging routine for the vehicle based upon least cost algorithms acrossthe fleet of PEVs within the service territory of the utility.

Once the vehicle receives the charge timing parameters, and the user hasplugged the vehicle into the electrical outlet, the vehicle will notdraw power from the outlet until the start time is achieved. Using theon-board clock of the vehicle, it begins charging according to the setparameters through direct control of the power electronics onboard thevehicle. If the user selects not to use the smart charging, then theonboard display within the vehicle may notify the use that they may bepaying a premium rate to charge the vehicle, with appropriateacknowledgement, specific to the utility-defined program.

If the user has chosen to roam charge the vehicle at a location otherthan their billing address, then the onboard system may ask the user toverify their location as determined by the GPS system. User verificationof address is then captured, transmitted to the vehicle system NOC, andon to the service provider's NOC for capture of a billing event dataset. This information is then sent on to the utility's billing system todebit the account of the user while crediting the account of thecustomer where the vehicle is being charged. This solution can beapplied within residential, commercial or municipal parking areas.

The onboard menu system may also allow the combination of roam chargemanagement with smart charge parameters to delay the start of vehiclecharging to match the tariff schedule of the user as defined by theutility program.

Within this approach, there is required modified software on theon-board vehicle system, a NOC to NOC interface between the vehiclesystems operations center and the service-provider's operations centerand a systems integration with the utility operational environment. Inthis manner, no end point hardware is required.

The systems and methods described above further permit numerousadditional applications. For example, utility operators may commanddistributes mobile energy resources as they might other resources on anetwork, to reduce load or to add capacity to the electrical grid. Onebenefit of integrating mobile energy storage in such a manner is thatmobile energy storage can be used to provide additional stability to theelectrical grid.

However, owners of mobile storage must choose to make their mobileenergy storage available to utility operators. Market applications ofthe system and method are therefore not only possible but highlydesirable. Moreover, incentives may be offered not only to individualconsumers but also to entities controlling more than one mobileresource, such as municipalites, car rental companies, taxi companies,or any owner of a fleet of PEVs. The systems and methods disclosedherein may thereby provide incentives related to fleet management. Theexamples described below may therefore be applicable to consumers and toentities, and the use of one in an example is not intended to excludeany applications or use with the other.

For example, with reference to FIG. 7, a parking lot, such as amunicipal parking lot at a mass transit station, can be enabled withcharging facilities 920 for mobile storage, such as PEVs 910. Further,the charging facilities (such as a “smart charger” device) may beenabled to identify the consumer or the specific resource, as describedabove. By identifying themselves to the charging facility, consumers maychoose to make the storage capacity of their mobile storage availablefor command as a distributed energy resource. A plurality of PEVs ableto be commanded by a utility operator may serve as a significant sourceof stored electricity available for dispatch, and can be dispatchedusing the systems and methods described above. Indeed, a number ofcommandable PEVs may collectively serve a utility as a “virtual powerplant,” providing a significant amount of energy available for dispatch.

The utility has a clear motivation to incentivize consumers toparticipate, because the amount of energy made available to the utilityfor dispatch is potentially substantial. The utility may reap financialbenefit from the arrangement, for example, because it may avoid bringingadditional generation capacity online to provide needed electricity. Theadditional capacity made available by numerous available distributedmobile resources may also aid in stabilizing the electrical grid throughthe availability of the stored capacity. The use of the methods oflevelizing and scheduling the requested dispatches conserves thecapacity of multiple distributed mobile resources, as well as minimizing“ripple” across the grid which may occur as a result of closelyoccurring dispatch starts or stops.

A variety of incentives may be offered. For example, a municipality mayoffer discounted mass transit tickets or other discounts to consumerswho park their PEVs at municipal parking lots and take publictransportation. Such discounts or coupons can be offered at particulartimes of day. The discounts or coupons can also be offered seasonally,or at any time when the need for the availability of additionalelectricity exists. For example, hot summer weather may create demandfor additional electricity to meet the needs of numerous HVAC units inoperation. Consumer incentives may be offered to draw PEV owners to maketheir mobile energy capacity available, for example, at a municipalparking lot. The utility stands to gain by purchasing the PEV storedcapacity at a fraction of the cost of bringing additional generatingcapacity online.

the owners of private parking facilities may also provide incentives toconsumers to make their mobile storage capacity available. For example,the owner of a parking lot at a shopping mall may offer consumers adiscount at a store or stores within the shopping mall to PEV owners whopark their vehicle at the shopping mall lot and make their mobilestorage capacity available for dispatch. In an embodiment, a consumerreceives a message on user interface 1100 offering a discount at aparticular store in a shopping mall in exchange for making the storagecapacity of his mobile device available for dispatch, for example, onSaturday between 10:00 AM and 2:00 PM. The consumer uses the userinterface 1100 to accept the offer, which causes data indicating suchacceptance to be transmitted back to the utility company or a thirdparty service provider. The consumer then drives to and parks at theshopping mall at a charging facility at the appointed time, providesidentification information to the charging facility, and makes hismobile resource available for dispatch, as described above. The shoppingdiscount may be applied in any number of ways. For example, theconsumer's identifying information may be provided electronically to thestore so that if the consumer makes a purchase, the discount isimmediately applied to the transaction. The consumer may be required tomake his mobile resource available for a minimum amount of time in orderto receive the discount.

The available energy may be used in any number of ways. For example, theenergy made available may be used to power a store, or a building. Themobile energy resources available in an office building parking lot, forexample, may be used to power the office building at peak prices times,or to at least decrease the load on the grid created by the building.Private parking facilities may require retrofitting of existing parking,or the provision of new parking, equipped with charging receptacles andthe means to identify consumers, as described above. However, theincentive of a utility to enter into economic arrangements with privateparking lot owners is high, and a utility may subsidize or pay entirelyfor the creation of new parking or the retrofitting of old parking toaccommodate PEVs as described herein.

Utilities and other entities may therefore use consumer incentives todraw mobile energy resources to specific locations or at specific times.Specific locations and times may be determined on the basis ofhistorical or predicted need, or on predicted availability of mobileenergy resources, using the method described above. Furthermore,incentives may be offered to PEV owners to discourage driving.

Incentives may be built around considerations such as environmentalfactors. For example, if a weather report indicates that a particularday is going to be smoggy, utilities may offer incentives to PEV ownersto park at municipal lots and ride public transportation. Similarly, autility or other entity may offer an incentive to consumers not to driveat all on such a day. Such incentives may be offered, for example, onthe same day at different price points. For example, on a day of heavysmog, consumers may be offered a lower incentive for parking at amunicipal lot and using public transportation, and a higher incentivefor staying home and not driving at all. It may be that consumerscapable of telecommuting may benefit more than other consumers. This mayin turn create pressure on employers to permit greater telecommuting,which may have an additional and incrementally greater environmentalbenefit. Similarly, the emissions of a PEV may depend on the state ofhealth of the battery, or on its level of charge. By takingenvironmental variables into account, the systems and methods may beused to provide behavioral incentives which tend to control autoemissions.

With reference to FIGS. 9 and 10, in an embodiment, the utility sends amessage to participating consumers in its service area. Such message mayappear, for example, on user interface 1100 in FIG. 9, which displaysmessages 1110 to a user. A consumer may choose to participate by makinga selection in user interface 1200. Similarly, a consumer may choose toparticipate by making her mobile resource available at a parkinglocation as described above.

One way to permit incentives to be included in the systems and methodsdescribed herein is to include a cost value in the step of determiningparticipation information. Cost values may be assigned by a utility, orby the owner of a mobile resource. Cost values may also be determinedalgorithmically. For example, an electrical utility may determine avalue for the energy discharged from, or used to charge, a mobile energyresource. As shown in FIG. 10, a utility may, for example, offer a lowercost value for electricity discharged from a mobile resource at adowntown office location, a higher cost value for electricity dischargedfrom a mobile resource at a mass transit parking lot, and a yet-highercost value for electricity discharged from a mobile resource at theowner's home (1220). The variable pricing thus provides an incentive forthe mobile resource owner to reduce driving (by only driving from hometo a public transportation lot) or to eliminate it (by not driving).Additional incentives are possible. For example, a utility may enterinto an agreement with a municipality, and may offer additionalincentives to ride public transportation, such as discounted masstransit tickets, or discounted parking at a mass transit station. Autility may thereby create incentives for mobile resource owners to maketheir mobile resources available at particular locations and atparticular times.

A utility may also enter into arrangements with other commercialentities, or with municipalities or other governmental organizations,and provide incentives to such larger entities. For example, a utilitymay offer an incentive, such as discounted electricity, or favorablebilling rates, to a municipality to make its vehicle fleet of mobileenergy resources available at a particular location or at a particulartime. The utility make provide levels of incentives, for example, inaccordance with the greatest need for electricity at on a particularday, or at a particular time. The utility may thus use incentives toalign the needs of a private or public entity with the needs of theutility to match energy supply to energy demand.

Utilities and other entities may apply other incentive schemes tomotivate consumer behavior. For example, a utility may offer asweepstakes style incentive, wherein, for example, the first fivethousand consumers who “enter”—by making the mobile energy capacityavailable for discharge—eligible for a prize of monetary value, or ofsome other value. A message 1110 may be sent to consumers, who may electto participate, for example, by making a selection in a user interface1220. Similarly, utilities seeking to motivate consumers to participatein a dispatch event may offer incentives in increasing steps until thedesired amount of participation capacity is met. For example, a utilityseeking to dispatch the amount of energy that may be stored in, forexample, one thousand PEVs, may offer to pay one price for energy, whichmay draw four hundred participants. The utility may later offer a higherprice, for which an additional three hundred participants may join. Theutility may offer a yet higher price for stored energy at a later pointin time, at which price the remaining three hundred participants aremotivated to make available their mobile stored energy capacity. A Dutchauction method may also be employed to determine the lowest clearingprice of energy desired by a utility. For example, a utility may send amessage, to be displayed in user interface 1100, stating its desired topurchase 5 MW of energy. Consumers may enter a value for their storedenergy and place bids 1230 through user interface 1100. The utility maythen purchase the desired 5 MW of energy at the lowest price at whichthe entire 5 MW is purchasable from the consumers who have placed bids.

Where owners of mobile energy resources are permitted to indicate a costvalue for their stored energy, utilities may respond to owner-indicatedvalues, and an electronic marketplace for stored energy may thus beenabled by the systems and methods herein described. For example, anowner may place a value at which the owner is willing to sell energy toa utility and make it available for discharge. The owner may indicate avalue through a user interface on the mobile resource, or through userinterface 1200. A utility seeking to dispatch energy from mobileresources may, for example, order the available resources in its serviceterritory by the average price of energy per resource, then selectresources for participation in a dispatch event from among the lowestprice set of resources for participation in a dispatch event from amongthe lowest price set of resources with a high probability ofaccomplishability. A utility may also discharge smaller amounts ofenergy from resources with higher priced energy and larger amounts ofenergy from higher priced energy. A utility may respond to owner-setprices by increasing or decreasing the price it is willing to pay topurchase stored energy from mobile resource owners, for example byincreasing the price it is willing to pay in order to gain access to alarger number of resources, or decreasing the price it is willing to payif a surplus of lower cost mobile storage is available. Mobile resourceowners may similarly vary the cost values which they assign to theirstored energy.

Cost values may be determined for other criteria as well. For example, avalue may be assigned based on the source of energy used to generate thestored electricity, such as a from a coal power plant, or from a nuclearpower plant, or from a renewable energy source such as wind or solar.The distribution of types of energy stored may be presented 1120, andmobile resource owners and utilities may, for example, selectpreferences for energy generated using cleaner forms of generation. Forexample, a utility may offer to purchase at a higher price stored energygenerated from renewable sources, such as energy generated from solarpanels on a resource owner's home. Similarly, a resource owner may, forexample, offer to purchase from the utility energy generated fromrenewable sources at a higher price, creating an incentive for theutility to use renewable energy over non-renewable sources.

A cost value for energy may also be determined algorithmically by thesystem. The cost value may take many variables into account, includingtime-of-day pricing, the price of gasoline, and the usage of gasoline incharging the battery. A value may also be assigned or determined basedon the carbon emissions associated with the energy stored. Similarly,carbon credits may also be assigned a value, or the system may beconfigured to account for carbon credits independent of an assignedvalue.

Utilities may thus provide incentives to reduce emissions, by providingan incentive to consumers to curtail driving. A utility may similarlyuse incentives offered to larger entities, such as companies, parkinglot owners, and municipalities, for similar aims. In addition, amunicipality may employ incentives in a similar fashion. For example, amunicipality wishing to decrease smog during a particular summer weekmay offer an incentive to consumers to curtail driving, or to theutility to similarly incentivize consumers. For example, a municipalitymay make its vehicle fleet available to the utility for dispatch inexchange for the utility offering incentives to consumers to curtaildriving, in order to drive down emissions.

The interface of FIGS. 9 and 10 may also be used to allow a utility toborrow stored energy in PEVs when they are plugged into the grid with apromise to return the energy at a later time with no consequence toeither the driving pattern or cost to the consumer. The interfaces canallow the consumer to define their parameters for participation alongwith appropriate economic incentives and verification procedures. Forinstance, the consumer might define that they always want enough energyto get home under all electric power and that they live 15 miles awayfrom work and leave work at 6 pm. The boundary condition defined by theconsumer provides a window of opportunity for the utility, and whenmultiplied by hundreds of thousands of available PEVs can amount tosignificant peak energy availability.

In addition to providing an interface to the incentive functionsdiscussed above, a user interface such as that shown in FIGS. 9 and 10can also be used to allow the owners of mobile energy resources such asPEVs to define their driving requirements such as typical morningdeparture time, typical return time and their tolerance for peak vs. offpeak pricing. A variation of this definition can include environmentalrequirements such that a consumer can specify the source of electricityused to replenish the stored energy in the PEV. Through softwarealgorithms, the utility can match their resource planning needs to theneeds of the consumer. It is possible to predict the daily load durationrequirements of the PEV by measuring the actual energy consumed by thedevice and normalizing to day of week or other patterns of usage. Thisinformation can then be aggregated within the control system to loadlevel a fleet of PEVs through staggered charge management routines. Amore-advanced version of this scenario includes getting informationdirectly from the energy storage device to state the need to the controlsystem at that point in time, again with a staggered approach to thefleet of PEVs to load level the system. From a utility's perspective,the load leveling may be highly locational in nature to deal withdistribution capacity and congestion issues. Therefore, the PEV must beprovisioned within the control system in such a way that localizedcapacity can be managed properly.

The timing of when the PEV replenishes its energy storage may becontrolled based upon a combination of time-of-use (TOU) pricingschedules and the integrated resource plan (IRP) of the electricutility. A schedule may be set for controlling the charge on or offstate that matches the TOU schedule or the goals of the IRP. Separately,due to the seasonal nature of available capacity in many areas, directprice signals may also be used alone or in conjunction with TOU pricingschedules to control when a PEV is re-charged. This would allow autility to provide unfettered re-charging during most of the year bututility-controlled during peak seasons. No human interaction orinterface required.

While the TOU schedule is simple and effective, it may not be adequatefor incentivizing consumers to participate in a smart charging program.Peak price schemas along with corresponding pricing signals broadcast tothe network of participating devices may be required. Another methodincludes using value-based pricing in which the PEV is separatelymetered and has a unique tariff apart from the other devices within thehome. This reduced tariff for the PEV (for example, $0.05 rather thanthe nominal $0.12) can provide a strong incentive to participate in asmart charging program while also optimizing the cost-benefit to theutility.

The gasoline tax is a major source of revenue for federal, state andlocal taxing authorities. Typically funds collected through the gas taxare applied (at least in part) toward maintaining roadways and othervehicle infrastructure. However, the increase adoption of PEVs willresult in decreased use of gasoline, and thus a decrease in theassociated tax revenues. To offset the loss of the ability to collectfunds to maintain the roadway infrastructure, a method is required totax the electricity used in powering PEVs.

The overall size of the tax may be determined by taking into account thefunds required to maintain infrastructure, spread over the expectedelectricity required to power the extant PEV fleet. In the event that acarbon tax is also imposed, the pollution component of PEV use may beincluded in the marginal cost of energy.

However, simply levying a tax on electricity used to charge PEVs isunfeasible, because of the PEV's capability of discharging—andreselling—its stored energy back to the grid. Systems and methods suchas those disclosed herein facilitate the tracking of the charging anddischarging of mobile storage connected to the power grid. For example,information about the tax associated with the charging and dischargingof electricity from a PEV'storage capacity may be stored by the PEVowner's electrical utility, or by a government entity, or at the pointof sale of electricity, or at the point of sale of gasoline for the PEV,or through a network communication system such as OnStar. Suchinformation may be transmitted, for example, between the PEV and thecharging receptacle, as described above. Similarly, a gasoline point ofsale ma also have the capability to transmit and receive informationfrom a PEV, for example, a WiFi, Bluetooth or Zigbee enabled device orhotspot, and may exchange such information with a PEV.

A range of options are available to a taxing authority for recapturinggasoline consumption tax revenue lost to PEV use. In an embodiment, theelectricity delivered into PEVs is differentiated from that delivered toother devices. A system such as that described above may permit theidentification of a PEV or its owner. A utility, or a data clearinghouse, or a credit card company, or a government entity, or anotherentity, may record data on how much electricity is delivered to aspecified PEV. The data regarding charging may be reconciled against anydischarges of energy to the grid performed by the identified consumer orPEV.

In an embodiment, a national transportation electricity accountingsystem may be provided. All electricity flowing into a uniquelyidentifiable PEV may be aggregated into a single account for thepurposes of the transportation tax. This electricity could be furthertagged with the appropriate regional tax information in the accountingsystem. The PEV electricity tax is a net tax, as electricity deliveredback to the grid will be substracted from the account so as toaccumulate an amount equal to that which is used for transportation. Theaccount will be separate from whatever process is used to pay theutility or utilities delivering the electricity. At the end of a givenperiod, be it weekly, monthly, or quarterly, the net electricity usedfor transportation may be taxed electronically by the relevant parties.

In an embodiment, a differentiated tax may be imposed on gasolinepurchased for a PEV owner than for a gasoline-only vehicle. Thedifferentiated tax may be lower or higher than the tax imposed for agasoline-only vehicle.

In an embodiment, a PEV owner may receive a reduction in his homeelectricity bill based on the tax imposed on electricity purchased forthe PEV.

While the invention has been described in detail and with reference tospecific embodiments thereof, it will be apparent to those skilled inthe art that various changes and modifications can be made thereinwithout departing from the spirit and scope thereof. Thus, it isintended that the present invention cover the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

1. A method for dispatching energy from a plurality of distributedstorage resources in a discharge event so that the energy stored in eachof the plurality of distributed resources is levelized, comprising:receiving, in a computer, a dispatch request comprising an amount ofpower required during a dispatch event and a duration of the dischargeevent; determining, in the computer, accomplishability of the dispatchrequest by: determining an aggregate rate of discharge for the pluralityof distributed energy resources based on the rates of discharge at whicheach of the individual resources of the plurality of distributedresources are capable of producing; determining if the determinedaggregate rate of discharge is sufficient to meet the amount of powerrequired to satisfy the dispatch request; determining if the determinedaggregate rate of discharge can be maintained at all times during thedispatch event, and if so, identifying the dispatch request asaccomplishable: causing, if the dispatch request is determined to beaccomplishable, the computer to determine the amount of energy to bedischarged from each of the plurality of distributed resources duringthe dispatch event so as to reduce the variance among the stored energylevels of the plurality of distributed energy resources; scheduling thedispatch of each of the plurality of distributed resources toparticipate in the dispatch event by: implementing a bin packingalgorithm to select the start and stop times of the discharge of each ofthe plurality of distributed resources during the dispatch event; andtilting the dispatch schedule by adding a fractional time offset tointervals in each bin used by the bin packing algorithm; sendingdispatch instructions to each of the plurality of distributed resourcesto participate in the scheduled dispatch event.
 2. The method of claim1, wherein the step of scheduling the dispatch of each of the pluralityof distributed resources further comprises: adding a ramp up time and aramp down time to each distributed resource participating in thedispatch event, ensuring that all ramp up and ramp down transitions ofthe plurality of distributed resources occur in pairs.
 3. The method ofclaim 1, wherein the step of scheduling the dispatch of each of theplurality of distributed resources further comprises: prioritizing theparticipation of each of the plurality of distributed resources in orderof their respective potential discharge duration potential.
 4. Themethod of claim 1, wherein the rates of discharge at which each of theplurality of resources are capable of discharging energy areapproximately the same.
 5. The method of claim 1, wherein the rates ofdischarge at which each of the plurality of resources are capable ofdischarging energy are not all the same.
 6. The method of claim 1,wherein the variance among the stored energy levels of each of theplurality of distributed energy resources is maximally brought to astate where each resource has a fraction of the total remaining energyof each of the plurality of distributed energy resources proportional toits discharge rate.
 7. The method of claim 1, wherein the amount ofenergy each of the plurality of distributed energy resource is capableof storing is approximately the same, and the sending dispatchinstructions to each of the plurality of distributed resources toparticipate in the scheduled dispatch event.
 2. The method of claim 1,wherein the step of scheduling the dispatch of each of the plurality ofdistributed resources further comprises: adding a ramp up time and aramp down time to each distributed resource participating in thedispatch event, ensuring that all ramp up and ramp down transitions ofthe plurality of distributed resources occur in pairs.
 3. The method ofclaim 1, wherein the step of scheduling the dispatch of each of theplurality of distributed resources further comprises: prioritizing theparticipation of each of the plurality of distributed resources in orderof their respective potential discharge duration potential.
 4. Themethod of claim 1, wherein the rates of discharge at which each of theplurality of resources are capable of discharging energy areapproximately the same.
 5. The method of claim 1, wherein the rates ofdischarge at which each of the plurality of resources are capable ofdischarging energy are not all the same.
 6. The method of claim 1,wherein the variance among the stored energy levels of each of theplurality of distributed energy resources is maximally brought to astate where each resource has a fraction of the total remaining energyof each of the plurality of distributed energy resources proportional toits discharge rate.
 7. The method of claim 1, wherein the amount ofenergy each of the plurality of distributed energy sources is capable ofstoring is approximately the same, and the accomplishable is nowunaccomplishable, providing an operator making the request anotification that the dispatch request is no longer accomplishable. 12.The method of claim 1, wherein the plurality of distributed resourcesare mobile energy resources and the step of determiningaccomplishability further comprises: receiving historical arrival anddeparture times at a location of each of the plurality of distributedresources; and determining the probability that a dispatch request canbe satisfied using plurality of distributed mobile resources based onthe historical arrival and departure times of the plurality ofdistributed resources.
 13. The method of claim 12, wherein theprobability determination is performed for regular time steps of theduration of the dispatch event to ensure that a sufficient number ofdistributed mobile resources will be available to satisfy the dispatchrequest during the duration of the dispatch event.
 14. The method ofclaim 13, further comprising: determining accomplishability using thehistorical data of the amount of stored energy available upon arrival ata location from each of the plurality of mobile distributed resources.15. The method of claim 14, further comprising: weighting a distributionof a predicted arrivals at that location with the historical amount ofstored energy available upon arrival of a mobile resource at a location;and, combining the weighted distribution with the energy available indistributed mobile resources that are actually available at a given timein order to compute accomplishability.
 16. The method of claim 13,further comprising: selecting the length of the time step length so asto minimize the number of distributed mobile resources that are removedfrom participation in the dispatch event while also minimizing thenumber of calculations resulting from the number of potentialdistributed mobile resources used to calculate the accomplishability.17. A method for dispatching energy from a plurality of distributedmobile storage resources in a discharge event so that the energy storedin each of the plurality of distributed mobile storage resources islevelized, comprising: causing a computer to receive a dispatch requestcomprising an amount of power required during a dispatch event and aduration of the dispatch event; receiving the historical arrival times,departure times, and stored energy available, of each of the pluralityof distributed mobile storage resources at a location; predicting thenumber of arrivals, departures, and the amount of stored energyavailable for the plurality of distributed mobile storage resourcesduring the dispatch event, the prediction being based, in part, on thehistorical arrival times, departure times, and the stored energyavailable for each distributed mobile storage resource; weighting adistribution of the predicted arrival times of mobile resources with thepredicted amount of stored energy available for the plurality ofdistributed mobile storage resources and combining the weighteddistribution with the number of mobile resources actually available;computing the accomplishability of the dispatch request by aggregatingthe combined weighted distribution at multiple time steps during thepredicted dispatch and determining if the aggregate rate of dischargecapability of each of the plurality of mobile resources is sufficient tomeet the amount of power required to satisfy the dispatch request ateach time step in the dispatch event, and if so, identifying thedispatch event as accomplishable; causing, if the dispatch event isdetermined to be accomplishable the computer to determine the amount ofenergy to be discharged from each of the plurality of distributed mobileresources during the dispatch event so as to maximally reduce thevariance among the stored energy levels of the plurality of distributedenergy resources; p1 scheduling the dispatch of each distributed mobilestorage resource of the plurality of distributed mobile storageresources to participate in the dispatch event using a bin packingalgorithm to select the start and stop times of the discharge of each ofthe plurality of distributed mobile storage resources; tilting thedispatch schedule by adding a fractional time offset to intervals ineach bin used in the bin packing algorithm; sending the dischargeinstructions to the plurality of distributed resources according to thedispatch schedule; adding a ramp up time and a ramp down time to eachdistributed mobile storage resource participating in the dispatch event,ensuring that all ramp up and ramp down transitions of the plurality ofdistributed mobile storage resources occur in pairs; and, repeating theaccomplishability step each time a new dispatch request is created orcancelled, and if a dispatch request that was previously determined notto be accomplishable is now determined to be accomplishable, providingan operator making the request a notification that the dispatch requestis now accomplishable, and if a dispatch request that was previouslydetermined to be accomplishable is now unaccomplishable, providing autility operator making the request a notification that the dispatchrequest is no longer accomplishable.